The present invention relates to a new and distinct cultivar of Heuchera and given the cultivar name of ‘Rio’. Heuchera is in the family Saxifragaceae. Heuchera ‘Rio’ came out of a planned breeding program to create red leaf Heuchera. It had great garden performance in spite of being red in the spring only. This new cultivar originated from a cross between Heuchera K201-2, a proprietary non-commercial hybrid, as the seed parent, and Heuchera K148-5, a proprietary non-commercial hybrid, as, as the pollen parent.
Compared to the seed parent, Heuchera K201-2, the new cultivar has leaves that are larger and more veiled and a bigger habit.
Compared to the pollen parent, Heuchera K148-5, the new cultivar is more veiled and has leaves that are a red amber to khaki rather than dark red burgundy.
Compared to Heuchera ‘Marmalade’, U.S. Plant Pat. No. 15,945, the new cultivar has larger leaves that are much less ruffled and less deeply lobed. The new cultivar has showier flowers.
Compared to Heuchera ‘Autumn Leaves’, U.S. Pat. No. 22,103, the new cultivar has greater vigor, a much bigger habit with many more crowns, and doesn't show leaf puckering.
This new Heuchera is uniquely distinguished by:                1. medium size leaves that change color depending on the temperature,        2. spring leaves are red; summer leaves are veiled and change from red to tan,        3. winter leaves are veiled olive green,        4. short flowering stems with showy white flowers,        5. reblooming all spring, summer, and fall,        6. excellent, multi-crowned, medium mounding habit,        7. and excellent vigor.        
This new cultivar has been reproduced only by asexual propagation (tip cuttings and tissue culture). Each of the progeny exhibits identical characteristics to the original plant. Asexual propagation by cuttings and tissue culture using standard micropropagation techniques with terminal and lateral shoots, as done in Canby, Oreg., shows that the foregoing characteristics and distinctions come true to form and are established and transmitted through succeeding propagations. The present invention has not been evaluated under all possible environmental conditions. The phenotype may change with variations in environment without a change in the genotype of the plant.